OPTIMIZATION OF TECHNOLOGICAL PARAMETERS OF NUTRITION MIXTURE FERMENTATION PROCESS WITH THE USE OF SPLINE INTERPOLATION

Abstract

A technology for producing a sourdough based on pure cultures of lactic acid bacteria without adding baker yeast and synthetic additives has been developed. It is proposed to use gluten-free soy and whole grain spelled flour as a nutritional mixture. The process of sourdough fermentation has been investigated in relation to the physicochemical parameters: the lifting force and titrated acidity. The experiments were conducted with temperatures of pure cultures symbiosis cultivation at 22 °C and 40 °C. To intensify the process of fermentation of a nutritious mixture, additional substrates were introduced into the sourdough cultures - lactulose, sorbitol, lactose and fructose in concentrations of 2, 4, 6 and 8 %. The efficiency of using the nucleotide adenosine triphosphate (ATP) at concentrations of 25, 50, 75, 100 mg/kg of flour in the sourdough culture samples has been investigated. The studied samples of sourdough cultures have a stable form of pasty consistency, acidity between 10 and 14 degrees Turner, ball lifting force no more than 25 minutes and humidity of 48–50 %.  Finished products were subject to organoleptic evaluation. According to the results of evaluating organoleptic parameters, as well as porosity, the best samples of functional bread were obtained by using the sourdough on lactulose base with the addition adenosine triphosphate as an energy source. By using mathematical model based on spline interpolation, the optimal technical parameters have been obtained to minimize the time of technological cycle of sourdough producing.  The optimal concentrations for lactulose and adenosine triphosphate nucleotide have been found, which are 4.34 % and 46.7 mg/kg of flour, respectively. Due to the peculiarities of the enzyme systems of lactic acid bacteria pure cultures, the introduction of the proposed technology for producing sourdough to the practice of producing functional bread will make it possible to obtain a high-quality product with a fermented carbohydrate component. The products obtained have a prolonged shelf life due to lactic acid. They also meet the established standards for physicochemical, organoleptic and microbiological indicators during the period of sale. This technology can be adapted by large and craft bakeries.